From the vantage point of emergency medicine, climate change is a clear and present danger to human health. One needn't be a climate scientist or pulmonary specialist to appreciate the impact of thick smoke on the tenuous lungs of a patient with chronic asthma. When mosquitoes move north into habitats made newly favorable by global warming, they will breed at higher rates and more effectively incubate vectors of tropical diseases previously unknown to these human populations. Superstorms are becoming the norm as warmer oceans evaporate more moisture into cloud formations and render cataclysmic events. Coral reefs and oyster beds have been decimated. Droughts, heat waves, floods, and wildfires dominate the news. So, where does the medical profession stand on all of this?

Doctors, nurses, hospital executives, and healthcare organization leaders have spoken out in the past about tobacco products, nuclear war, genocide, and other matters that cause human suffering. Climate change has become the greatest challenge facing the health and safety of people on Earth. The situation demands science, education, policy, enforcement, and most of all, the collective will of the "haves" who are in control of societies, economies, and governments.

We are doctors who care for our patients, and the planet that is their home. We believe that humans are making changes to our environment that soon may become irreversible. We fully understand that the science of climate change is evolving as experts make more observations, perform more research, derive more data, and do their best to make reasonable interpretations. The controversies are apparent, but the logic of preserving what we can and trying to avoid depletion of resources and irrevocable changes to our planet that will affect human health adversely are truths to us. We need to take a "doctor's approach" because we believe we are facing a sick patient and want emphatically to bring human health to the front of the discussion. We believe that evidence points to the fact that humans are altering the environment in a way that causes global warming, widespread pollution, destruction of habitats and species, and everything that comes with these. From that belief comes logical health implications that we cannot ignore.

This is a doctor's approach. We care about you. If your chest was hurting, you couldn't breathe, and your pulse was undetectable, we wouldn't ponder the situation. We'd do everything possible to make an accurate diagnosis and try to save your life. We'd act fast, because moments count. Should we be any less concerned about our planet?

We rely upon the science of others to understand predictions of global climate change, but we don't need others to explain the health effects. We treat them. Every day in emergency departments around the world are seen patients suffering from post-flood diarrhea, starvation, heatstroke, smoke inhalation, and insect-borne infectious diseases. Climate change is a "force multiplier" and adding to the burden of disease, and it will soon affect people you know, and hundreds of millions you have never met. Sadly, the least fortunate of them will suffer the most.

Part of the problem to date with science communications on climate change has been failure to identify an immediate health threat. No one ever thinks it is going to happen to them. The U.S. national fire season of 2017 should put that thinking to rest. What more do we need to change the way we live and consume our resources? We want everyone to form an opinion, and to act on their knowledge and conscience. Some people will disagree with our premise. We urge them to learn more. If the prospect of change seems too daunting or efforts appear futile, then we need to find ways to create hope and personal energy sufficient to motivate action. We need to harness the best minds in our healing industry to determine how best to gather data, influence productive efforts, and face climate change head on.

I know a lot about wilderness medicine. It's impossible to imagine wilderness medicine without the wilderness. While we support the environmentalists and work among them, it's our duty to emphasize the health implications of climate change and be recognized for our expertise. Climate denial has become untenable, so we need to stand our ground on the issue.

What should health professionals do? Without a doubt, they should become involved. I recently heard a climate expert opine that perhaps the only hope left to persuade the general population that climate change is a critical issue is to rely upon the health profession as being one of unequivocal trust. Here are suggestions for action:

Learn about climate change, and in particular global warming. Other topics include destruction of habitats, sea level rise, food and water insecurity, migration of infectious disease vectors, climate justice, and human population growth and dynamics.

Be conscious of your personal energy use.

Analyze the energy use of your organization. Use best practices to use sustainable energy and lower consumption. Don't pollute.

Support environmental and climate education at all levels, notably in medical professional schools. Within this education should be an emphasis on the health impacts broadly defined – clinical, economic, and societal. Climate change is a public health issue, and should be featured prominently.

Perform and support excellent science and assemble evidence about the effects of climate change on human health.

Help the people and organizations that are trying to help us. Provide services and opinions to non-medical actors and entities engaged in environmental efforts intended to save the planet and its inhabitants.

Investigate and join reputable groups so that there can be strength in numbers. An example for medical societies is the Medical Society Consortium on Climate and Health. For hospitals, learn about Global Green and Healthy Hospitals.

Now begins the most important work of our lives. We cannot fail in this effort.